0-3-1 Heavy Shells dealing 2 damage to Leads instead of 1
Extra Damage to Lead is a projectile behavior characterized by dealing more damage than that tower's base damage to Lead Bloon properties per hit. It is part of the damage types family.
Extra Damage to Lead is represented on Bloons Wiki as 
, the upgrade icon for Heavy Shells in Bloons TD 6, which conveniently deals extra damage to Leads and looks like a lead-based impact. Extra Damage to Lead is simply a subset of Extra Damage 
. Only few unique upgrades are known to exist in Bloons TD 6, and all are added in later updates: Heavy Shells and its later upgrades, submerged 4-2-0 Reactors, Lead to Gold and Ultra-Juggernaut's main Juggernaut ball.
Gwendolin's Level 17 "Heat it Up" Passive Ability also allows affected towers to deal extra damage to Leads.
All attacks require an upgrade to deal more than one damage to Lead per hit. Oddly enough, it takes at least Tier 3 upgrades to unlock this type of property. This Extra Damage also applies to DDTs. In BTD6 this Extra Damage also applies Dreadbloon itself, which share much of the same properties with Leads.
Towers that gain Extra Damage to Lead[]
BTD6[]
Towers:
- 4-2-0 Bloontonium Reactor and 5-2-0 Energizer's radiation
- Heavy Shells and subsequent upgrades
- Lead to Gold and subsequent upgrades
- Ultra-Juggernaut's main ball
Buffs:
- Gwendolin's Heat it Up when Level 17+
BTDB2[]
Tower:
- Ultra-Juggernaut
- Heavy Shells and subsequent upgrades
- Arcane Spike and Archmage
- Lead to Gold and subsequent upgrades
Heroes:
- Scientist Gwendolin's main attack and Heat it Up buffs.
